Active DNA repair pathways are crucial for preserving genomic integrity and are likely among the complex mechanisms involved in the normal development of preimplantation embryos. MicroRNAs (miRNA), short non-coding RNAs, are key regulators of gene expression through the post-transcriptional and post-translational modification of mRNA. The association of miRNA expression with infertility or poly...

Adherens junction formation is fundamental for compaction and trophectoderm differentiation during mammalian preimplantation development. We recently isolated an IQGAP-2 cDNA from a differential display-polymerase chain reaction screen of bovine preimplantation developmental stages. IQGAP-1 and -2 proteins mediate E-cadherin-based cell-to-cell adhesion through interactions with beta-catenin and...

Control of growth and differentiation during mammalian embryogenesis is regulated by growth factors from embryonic and/or maternal sources. Cytokines are polypeptide growth factors that are released by a variety of activated immune and nonimmune cells. To identify novel members of the cytokine family that could be involved in the growth and differentiation of the preimplantation embryo, we stud...

Parathyroid hormone-like hormone (PTHLH) was first identified as a parathyroid hormone (PTH)-like factor responsible for humoral hypercalcemia in malignancies in the 1980s. Previous studies demonstrated that PTHLH is expressed in multiple tissues and is an important regulator of cellular and organ growth, development, migration, differentiation, and survival. However, there is a lack of data on...

Preimplantation development shifts from a maternal to embryonic programme rapidly after fertilization. Although the majority of oogenetic products are lost during the maternal to embryonic transition (MET), several do survive this interval to contribute directly to supporting preimplantation development. Embryonic genome activation (EGA) is characterized by the transient expression of several g...

With readily available transcriptome-wide data, understanding the role of each expressed gene is an essential next step. Although RNAi technologies allow for genome-wide screens in cell culture, these approaches cannot replace strategies for discovery in the embryo. Here we present, for the first time, a knockdown screen in mouse preimplantation embryos. Early mammalian development encompasses ...

Objective: To compare the efficiency of two different sequential media for the cultivation of sibling embryos until the blastocyst stage. Design: A prospective analysis was conducted on 113 ART cycles with the indication of severe male factor infertility in Istanbul Memorial Hospital ART and Genetics Unit. Setting: After insemination, oocytes were randomly divided into two groups and cultured w...

Preimplantation embryos from a variety of mammalian species contrast markedly in their response to culture in vitro. Murine preimplantation embryos display a wider tolerance than other mammalian species to culture environments, and this has contributed to the development of several effective defined culture media. Embryo coculture on somatic cells remains the most effective method of supporting...

Gonadotrophin-releasing hormone (GnRH) regulates gonadotrophin biosynthesis and release in the anterior pituitary via specific receptors. Extrapituitary expression and action of GnRH have been demonstrated in several species. A possible role for GnRH in preimplantation embryonic development, endometrial preparation, and the implantation process has been previously suggested. Moreover, the prese...

background: this study was designed to develop a new co-culture system, assess the effect of luteinizing hormone (lh) using sequential media to promote development and increase the quality of 2-cell murine embryos through the 8-16 cell stage to morula and blastocyst stages. materials and methods: monolayers for co-culture were prepared from ovine oviduct epithelial cells (ooec) in dmem/f12 medi...